The teenager also posted a partial Spreadsheet filled with the supposed names, email addresses, phone numbers and Social Security numbers (SSNs) of 2,611 former and current government intelligence officials.

The hacker, who describes himself as an American high school student, called the New York Post to describe his exploits.

According to the teenage hacker, Brennan's private email account held a range of sensitive files, which includes:

His 47-page application for top-secret security clearance

Social Security numbers (SSNs) and personal information of more than a dozen top US intelligence officials

A government letter discussing "harsh interrogation techniques" used on terrorist suspects

Sensitive Information Leaked

The teenage hacker operates with under the Twitter name "Crackas With Attitude" with Twitter handle @_CWA_. He confirmed the Post that he also controlled the Twitter handle, @phphax.

Before suspended, the @_CWA_ account released what it claimed was alleged personal information of 2,611 former and current government intelligence officials on Twitter Monday afternoon. The data includes:

Phone numbers

Social Security Numbers

E-mail addresses

A level of security clearance and employment status in some cases

The hacker also tweeted screenshots of one of the sensitive documents that he claimed to discover inside the email account and show a fax from the CIA Office of General Counsel.

How Did the Hacker Break into The CIA Personal Email?

The hacker said he reportedly gained access to the AOL account of CIA Director via a social engineering scam in which he posed as a Verizon employee to trick another employee into revealing Brennan's personal details.

Using that information the hacker was able to reset the password on Brennan's personal AOL account repeatedly as the chief fought to regain its control. The Brennan’s account has since been disabled.

Federal agencies including the FBI are now investigating the matter. According to one of the law enforcement sources, criminal charges on the hacker are possible.

"I cannot believe he did this to the head of the CIA," the source told the Post. "[The] problem with these older-generation guys is that they do not know anything about cyber security, and as you can see, it can be problematic."

However, the two anonymous American officials said that no classified information was hacked and compromised as a result of the hack.

Of course, this isn't the first time the hackers have targeted any CIA official. Just six months ago, former-Secretary of State Hillary Clinton was targeted by hackers due to storing classified emails on her personal servers.